1. Field of the Invention
The present invention is related to LCD apparatus having an ESD protection member, and particularly, to have an extra metal cover having flange designed as the ESD protection member so as to prevent the LCD modules from any ESD attack.
2. Description of the Prior Art
The phenomena of area having high electrostatic charges concentration flow to a region having low concentration or region of having opposite types is generally called electrostatic discharge (hereinafter called ESD). The display and periphery driving circuit of liquid crystal display module may be attacked or affect by an event of ESD. The ESD may cause the display to be damaged, such as the thin traces on board are melted or volatile, or resistance varies, or oxide layer is being punch-through and/or the microprocessor or controller therein runs with malfunction. ESD may be a main factor that makes the electron devise encounter electrical overstress (EOS), which often causes permanent damage to the integral circuit (IC) thereby causing the device failed.
In recent years, with the advent of consuming electronic device having various fancy features and functions become consensus and a trend for manufacturers and designers. Slim, compact, and lightweight designs have become the mainstream of the market and even the norms of the industry. With regard to mobile communication devices such as cellular phones, variety of rich tone rings and colorful displays have been considered by consumers as the very basic features. Moreover, digital camera embedded in mobile phone is no longer a rarity. To lure consumer discarding his old phone but buying a newly mobile phone, manufacturers often design phones with ergonomics and a much advertised feature. For instance, foldable cell phones embedded with digital camera of mega-pixels, or PDA (personal digital assistant) and/or MP3.
In response to the LCD display of cellular phone demanded with extreme high resolution thereby the transparent conductive traces made of indium tin oxide (ITO) is thinner and thinner. This may further weaken the ESD prevent ability. Generally, the ESD attacking ITO often comes from the seams or the joints of the mechanism, in results, the display module of the phone is damaged or program to be crashed.
In particular, to those phones having a surface lens formed on upper board thereof, the damage caused by ESD is more severe. It is due to the fringes of the surface lens usually plated with a thin metal film. While ESD invades the thin metal film, the charges attacks the ITO. Thus, to prevent the LCD module from ESD attack, the glass substrate is usually mounted with capacitors or ESD protective elements according to prior art. However, the problems, like glass brittle due to wire bonding may occur. Other conventional technique published is by mounting ESD protective elements on the flexible wire bus. However, ESD attack often be found through the ITO to the inner portion of IC. Still, another technique disclosed is by forming a droplet pattern with tips on the print circuit board (PCB) of the LCD module through patterning process.
Another prior art of about ESD prevention is disclosed by Taiwan, R.O.C., patent publication No. 541858 issued to Wintek corporation, which discloses a special ITO route. In brief, referring to FIG. 1, the ITO traces formed at contacts of IC and the glass substrate are in accordance with a special area distribution function coated beneath the IC. The ITO routes 10 are formed around the glass substrate 5 and connected with ground VSS. The reset pin is then connected in series with a resistor having high resistance. The interface is also enclosed by the VSS.
The present invention provides a newly perspective structure, with which ESD problems can be overcome but without using ESD protection devices and/or special ITO route design.